A Slight Delay in the Onset of Conservation May Bring about an Abrupt Increase of Extinction Risk: Perturbation Experiments in an Ecological Lattice Model

摘要

We carry out perturbation experiments for both extinction and recovering processes by Monte-Carlo simulations on a finite square lattice, Simulations are tried out by two different methods: local and global interactions. We explore fluctuation enhancement which means the degree of population uncertainty. We find the following results. When an endangered species is recovered, FE strongly emerges. By a slight delay of conservation policy, FE becomes high and the recovering process often fails. These results are remarkable for local interaction. We discuss the issue from the assumption that the protection case may be help towards populations against an endangered species.